Communications Jacks Having Flexible Printed Circuit Boards With Low-Coupling Jackwire Contacts Mounted Thereon

ABSTRACT

Communications jacks include at least first through third jackwire contacts and a flexible substrate that has a first finger and a second finger. The first jackwire contact and the third jackwire contact are each mounted on the first finger and the second jackwire contact is mounted on the second finger.

CROSS-REFERENCE TO RELATED APPLICATIONS

The present application claims priority under 35 U.S.C. §119(e) fromU.S. Provisional Patent Application Ser. No. 61/699,903, filed Sep. 12,2012 and to U.S. Provisional Patent Application Ser. No. 61/697,955,filed Sep. 7, 2012, the disclosure of each of which is herebyincorporated herein by reference in its entirety.

FIELD OF THE INVENTION

The present invention relates generally to communications connectorsand, more particularly, to communications jacks.

BACKGROUND

Computers, fax machines, printers and other electronic devices areroutinely connected by communications cables to network equipment suchas routers, switches, servers and the like. FIG. 1 illustrates themanner in which a computer 10 may be connected to a network device 30(e.g., a network switch) using conventional communications plug/jackconnections. As shown in FIG. 1, the computer 10 is connected by a patchcord 11 to a communications jack 20 that is mounted in a wall plate 18.The patch cord 11 comprises a communications cable 12 that contains aplurality of individual conductors (e.g., eight insulated copper wires)and first and second communications plugs 13, 14 that are attached tothe respective ends of the cable 12. The first communications plug 13 isinserted into a plug aperture of a communications jack (not shown) thatis provided in the computer 10, and the second communications plug 14 isinserted into a plug aperture 22 in the front side of the communicationsjack 20. The contacts or “blades” of the second communications plug 14are exposed through the slots 15 on the top and front surfaces of thesecond communications plug 14 and mate with respective “jackwire”contacts of the communications jack 20. The blades of the firstcommunications plug 13 similarly mate with respective jackwire contactsof the communications jack (not shown) that is provided in the computer10.

The communications jack 20 includes a back-end wire connection assembly24 that receives and holds insulated conductors from a cable 26. Asshown in FIG. 1, each conductor of cable 26 is individually pressed intoa respective one of a plurality of slots provided in the back-end wireconnection assembly 24 to establish mechanical and electrical connectionbetween each conductor of cable 26 and a respective one of a pluralityof conductive paths (not shown in FIG. 1) through the communicationsjack 20. The other end of each conductor in cable 26 may be connectedto, for example, the network device 30. The wall plate 18 is typicallymounted on a wall (not shown) of a room of, for example, an officebuilding, and the cable 26 typically runs through conduits in the wallsand/or ceilings of the office building to a room in which the networkdevice 30 is located. The patch cord 11, the communications jack 20 andthe cable 26 provide a plurality of signal transmission paths over whichinformation signals may be communicated between the computer 10 and thenetwork device 30. It will be appreciated that typically one or morepatch panels, along with additional communications cabling, would beincluded in the communications path between the cable 26 and the networkdevice 30. However, for ease of description, in FIG. 1 the cable 26 isshown as being directly connected to the network device 30.

In the above-described communications system, the information signalsthat are transmitted between the computer 10 and the network device 30are typically transmitted over a pair of conductors (hereinafter a“differential pair” or simply a “pair”) rather than over a singleconductor. An information signal is transmitted over a differential pairby transmitting signals on each conductor of the pair that have equalmagnitudes, but opposite phases, where the signals transmitted on thetwo conductors of the pair are selected such that the information signalis the voltage difference between the two transmitted signals. The useof differential signaling can greatly reduce the impact of noise on theinformation signal.

Various industry standards, such as the TIA/EIA-568-B.2-1 standardapproved Jun. 20, 2002 by the Telecommunications Industry Association,have been promulgated that specify configurations, interfaces,performance levels and the like that help ensure that jacks, plugs andcables that are produced by different manufacturers will all worktogether. By way of example, the TIA/EIA-568-C.2 standard (August 2009)is designed to ensure that plugs, jacks and cable segments that complywith the standard will provide certain minimum levels of performance forsignals transmitted at frequencies of up to 250 MHz. Most of theseindustry standards specify that each jack, plug and cable segment in acommunications system must include eight conductors 1-8 that arearranged as four differential pairs of conductors. The industrystandards specify that, in at least the connection region where thecontacts (blades) of a plug mate with the jackwire contacts of the jack(referred to herein as the “plug jack mating region”), the eightcontacts in the plug are generally aligned in a row, as are thecorresponding eight contacts in the jack. As shown in FIG. 2, whichschematically illustrates the positions of the jackwire contacts of ajack in the plug-jack mating region, under the TIA/EIA 568 type Bconfiguration (which is the most widely followed), conductors 4 and 5comprise differential pair 1, conductors 1 and 2 comprise differentialpair 2, conductors 3 and 6 comprise differential pair 3, and conductors7 and 8 comprise differential pair 4.

Unfortunately, the industry-standardized configuration for the plug-jackmating region that is shown in FIG. 2, which was adopted many years ago,generates a type of noise known as “crosstalk.” As is known to those ofskill in this art, “crosstalk” refers to unwanted signal energy that isinduced onto the conductors of a first “victim” differential pair from asignal that is transmitted over a second “disturbing” differential pair.Various techniques have been developed for cancelling out the crosstalkthat arises in industry standardized plugs and jacks. Many of thesetechniques involve providing crosstalk compensation circuits in eachcommunications jack that introduce “compensating” crosstalk that cancelsout much of the “offending” crosstalk that is introduced in the plug andthe plug-jack mating region due to the industry-standardized plug-jackinterface. In order to achieve high levels of crosstalk cancellation,the industry standards specify pre-defined ranges for the crosstalk thatis injected between the four differential pairs in each communicationplug, which allows each manufacturer to design the crosstalkcompensation circuits in their communications jacks to cancel out thesepre-defined amounts of crosstalk. Typically, the communications jacksuse “multi-stage” crosstalk compensation circuits as disclosed, forexample, in U.S. Pat. No. 5,997,358 to Adriaenssens et al. (hereinafter“the '358 patent”), as multi-stage crosstalk compensating schemes canprovide significantly improved crosstalk cancellation, particularly athigher frequencies. The entire contents of the '358 patent are herebyincorporated herein by reference as if set forth fully herein.

BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 is a schematic drawing that illustrates the use of communicationsplug and jack connectors to connect a computer to a network device.

FIG. 2 is a schematic diagram illustrating the TIA/EIA 568 type Bmodular jack contact wiring assignments for a conventional 8-positioncommunications jack as viewed from the front opening of the jack.

FIG. 3 is a perspective view of a communications jack according toembodiments of the present invention.

FIG. 4 is a schematic perspective view of a portion of a communicationsinsert of the communications jack of FIG. 3.

FIG. 5 is a side view of one of the jackwire contacts of thecommunications insert of FIG. 4.

FIG. 6 is a schematic side cross-sectional view of the front portion ofthe communications insert of FIG. 4 taken along the longitudinal lengthof one of the jackwire contacts.

FIG. 7 is a perspective view of the rear portion of the jack of FIG. 3with the terminal housing removed to expose the output terminals of thejack.

FIG. 8 is a schematic plan view of a flexible printed circuit board ofthe communications insert of FIG. 4.

FIG. 9 is a schematic plan view of a spring of the communications insertof FIG. 4.

FIG. 10 is a schematic perspective view of a portion of a flexibleprinted circuit board according to further embodiments of the presentinvention that may be used in the communications jack of FIG. 3.

DETAILED DESCRIPTION

Pursuant to embodiments of the present invention, communications jacksare provided that may have very short signal current carrying pathsalong the jackwire contacts thereof as compared to communications jacksthat use conventional spring jackwire contacts. Herein, the term “signalcurrent carrying path” refers to the physical distance that acommunications signal travels along a structure (e.g., a jackwirecontact) when the signal passes through the structure on the way to itsdestination. The signal current carrying paths through the jackwirecontacts of the jacks according to embodiments of the present inventionmay be shortened because, for example, the jackwire contacts may bemounted on a resilient substrate such as a flexible printed circuitboard. A separate spring may be used to activate the jackwire contacts.The combination of the flexible structure and the separate spring (ifprovided) may be used to resiliently mount the jackwire contacts,thereby allowing the use of shorter jackwire contacts that have reducedor even virtually no resilience, while still ensuring that each jackwirecontact maintains the requisite contact force against the respectiveblades of a mating communications plug. By shortening the signal currentcarrying path through the jackwire contacts, the crosstalk betweenadjacent contacts may be advantageously reduced. The jackwire contactsmay also be mounted in a staggered pattern on the flexible printedcircuit board in order to further reduce crosstalk between adjacentjackwire contacts.

In some embodiments, the flexible printed circuit board may include aplurality of fingers. The jackwire contacts may be mounted on thesefingers, and the fingers may allow each jackwire contact to deflectsubstantially independently of adjacent jackwire contacts when thejackwire contacts are engaged by the blades of a mating communicationsplug. In some embodiments, multiple contacts may be mounted on the samefinger, which may facilitate initiating inductive crosstalk compensationat a very short distance (and hence delay) from the plug contact regionof the jackwire contacts (i.e., from the plug-jack mating point). Thejacks may comprise, for example, RJ-45 or RJ-11 jacks, althoughembodiments of the present invention are not limited thereto.

Embodiments of the present invention will now be described withreference to the accompanying drawings, in which exemplary embodimentsare shown. In particular, FIG. 3 is a perspective view of acommunications jack 100 according to embodiments of the presentinvention. FIG. 4 is a schematic perspective view of a portion of acommunications insert 120 for the communications jack 100. FIG. 5 is aside view of one of the jackwire contacts of the communications insert120. FIG. 6 is a schematic side cross-sectional view of the frontportion of the communications insert 120 taken along the longitudinallength of one of the jackwire contacts thereof. FIG. 7 is a perspectiveview of the rear portion of the jack 100 with the terminal housingremoved to expose the output terminals of the jack. FIG. 8 is aschematic plan view of a flexible printed circuit board that is part ofthe communications insert 120. FIG. 9 is a schematic plan view of aspring of the communications insert of 120. Finally, FIG. 10 is aschematic perspective view of a portion of a flexible printed circuitboard according to further embodiments of the present invention that maybe used in the communications jack of 100.

As shown in FIG. 3, the jack 100 includes a housing 110. In the depictedembodiment, the housing 110 includes a jack frame 112, a cover 116 and aterminal housing 118. The jack frame 112 includes a plug aperture 114for receiving a mating communications plug. The housing components 112,116, 118 may be conventionally formed and need not be described indetail herein. Those skilled in this art will recognize that otherconfigurations of jack frames, covers and terminal housings may also beemployed with the present invention, and that the housing 110 may havemore or less than three pieces. It will also be appreciated that thejack 100, when mounted for use, is typically rotated 180 degrees aboutits longitudinal axis from the orientation shown in FIG. 3. In thediscussion that follows, the x-direction in FIG. 3 is referred to as thelongitudinal direction, the y-direction in FIG. 3 is referred to as thelateral direction, and the z-direction in FIG. 3 is referred to as thevertical direction. In the discussion that follows, the relationships ofthe components of jack 100 with respect to each other will be describedwith respect to the orientation illustrated in the figures forconvenience.

FIG. 4 illustrates a portion of a communications insert 120 of the jack100. The forward portion of the communications insert 120 is receivedwithin an opening in the rear of the jack frame 112. The bottom of thecommunications insert 120 is protected by the cover 116, and the top ofthe communications insert 120 is covered and protected by the terminalhousing 118. The communications insert 120 further includes a flexibleprinted circuit board 130, a plurality of jackwire contacts 140, aplurality of dielectric contact carriers 150, a spring 160 (see FIG. 9)and a plurality of output contacts 170 (see FIG. 7), each of which willbe discussed in further detail below. A substrate 122 (see FIG. 6) maybe provided in some embodiments that may be disposed between the cover116 and the flexible printed circuit board 130.

As shown best in FIGS. 4, 6 and 8, the flexible printed circuit board130 may comprise an elongated printed circuit board that is formed of aflexible material that may be bent in various ways. In the depictedembodiment, the flexible printed circuit board 130 includes a pair oflongitudinal slots 133 that “decouple” a front portion 131 of theflexible printed circuit board 130 from the back portion 132. Inparticular, the slots 133 allow the front portion 131 of the flexibleprinted circuit board 130 to be moved within a range withoutsubstantially impacting the rear portion 132, and vice versa. As shownin FIG. 6, the slots 133 allow the front portion 131 of flexible printedcircuit board 130 to be disposed at a lower level (vertically) withinthe jack housing 110 than the rear portion 132. While the communicationsinsert 120 includes a single flexible printed circuit board 130, it willbe appreciated that in other embodiments two or more printed circuitboards (or other substrates) may be provided. For example, the frontportion 131 of the flexible printed circuit board 130 could be replacedwith a first flexible or non-flexible printed circuit board and the rearportion 132 of flexible printed circuit board 130 could be replaced witha second flexible printed circuit board in other embodiments of thepresent invention.

The flexible printed circuit board 130 may include one or moredielectric layers that may have conductive traces and/or other elementsdisposed on one or both sides thereof, as is known to those of skill inthe art. The flexible printed circuit board 130 may be used as atransmission medium for signals that pass between the jackwire contacts140 and the respective output contacts 170 of the jack 100, as will beexplained in more detail with reference to FIG. 8. The flexible printedcircuit board 130 may also include a plurality of crosstalk compensationcircuits disposed thereon or therein, which will also be discussed inmore detail below with reference to FIG. 8.

As is further shown in FIG. 4, the flexible printed circuit board 130includes a lateral slot 134 that extends between the pair oflongitudinally-extending slots 133. Additionally, a plurality oflongitudinal slots 135-1 through 135-7 are provided in the front portion131 of the flexible printed circuit board 130 that define eightrearwardly facing fingers 136-1 through 136-8. Herein, when thecommunications jacks according to embodiments of the present inventioninclude multiple of the same components, these components may bereferred to individually by their full reference numerals (e.g., finger136-4) and may be referred to collectively by the first part of theirreference numeral (e.g., the fingers 136). Likewise, six longitudinalslots 137-1 through 137-6 are provided in the rear portion 132 of theflexible printed circuit board 130 that define a plurality of additionalfingers 138-1 through 138-6. As shown in FIG. 4, fingers 138-1, 138-2,138-5 and 138-6 are generally longitudinally-extending fingers that faceforwardly, while fingers 138-3 and 138-4 have both longitudinal andlateral components. Herein, a “finger” on a substrate such as a flexibleprinted circuit board refers to a cantilevered portion of the substrate,regardless of the particular shape. Thus, it will be understood that thefingers 136, 138 need not be elongated fingers.

The eight fingers 136 may move relatively independent of each other suchthat each finger 136 may be depressed a different distance downwardlywhen the jack 100 is mated with a communications plug. Likewise, the sixfingers 138 may also move relatively independent of each other in thissituation. The ability of each finger 136, 138 to move relativelyindependent of the other fingers 136, 138 may improve the performanceand reliability of the jack 100.

In particular, various industry standards specify certain physicalcharacteristics that must be met for a communications plug to qualify asan industry-standardized communications plug. The physicalcharacteristics specified in these standards include the distances thatportions of the plug blades must be from the bottom and front surfacesof the plug housing (when the plug is oriented as shown in FIG. 6), andthe industry standards specify ranges for these distances to accommodatemanufacturing tolerances. Because ranges are specified, a communicationsplug may be industry-standard compliant even though its plug blades arenot all the same distance from the bottom and/or front surfaces of theplug housing (i.e., the blades may be offset from each other in thelongitudinal direction and/or the vertical direction).

When a communications plug that has plug blades that are offset fromeach other is inserted into the jack 100, certain of the plug blades mayengage their respective jackwire contacts 140 of jack 100 sooner thanother of the plug blades. The subset of the jackwire contacts 140 thatare initially engaged in this fashion exert a downward force on theflexible printed circuit board 130. If the flexible printed circuitboard 130 did not include the fingers 136, 138, as the flexible printedcircuit board 130 is pushed downwardly, it would draw the remainingjackwire contacts 140 downward as well (i.e., the jackwire contacts 140that had not yet been engaged by their respective plug blades), pullingthese jackwire contacts 140 away from their respective plug blades. As aresult, some of the jackwire contacts 140 will exert a greater contactforce against their respective plug blades (namely the jackwire contacts140 that are initially contacted by the offset plug blades) than willother of the jackwire contacts 140. If the flexible printed circuitboard 130 does not include the fingers 136, 138 this effect may bemagnified such that, under certain circumstances, some of the jackwirecontacts 140 may exhibit poor contact force (or even no contact force atall) against their respective plug blades. However, by providing thefingers 136, 138 on the flexible printed circuit board 130, the degreeto which the movement of a first of the jackwire contacts 140 changesthe position of other of the jackwire contacts 140 may be reduced, andhence the jack 100 may be less susceptible to performance degradationwhen used with plugs that have plug blades that are offset from eachother in the longitudinal and/or vertical directions.

As shown best in FIGS. 4-6, eight low coupling jackwire contacts 140-1through 140-8 are mounted in two rows on a top surface of the flexibleprinted circuit board 130. Herein, a “jackwire contact” refers to aconductive contact structure of the jack that is mounted in or on astructure so as to extend into the plug aperture of the jack. Eachjackwire contact is configured to mate with a blade (or other contactstructure) of a communications plug that is received within the plugaperture 114 of the jack 100.

As shown in FIG. 5, each jackwire contact 140 has a first end 142, asecond end 146 and a middle section 144 that includes a “plug contactregion” (i.e., the portion of the jackwire contact 140 that engages theblade of a mating plug that is received within the plug aperture 114 ofjack 100). The jackwire contacts 140 may be formed of, for example, aresilient metal such as beryllium-copper or phosphor-bronze, or anon-resilient metal such as copper or gold-plated copper. In someembodiments, the jackwire contacts 140 may comprise substantially rigidcontacts, meaning that the jackwire contacts 140 do not flex more than ade minimis amount when engaged by the respective blades of a mating plugduring normal use of the jack 100. The first end 142 of each jackwirecontact 140 is mounted to extend upwardly from a respective one of thefingers 136. The first end 142 of each jackwire contact 140 may extendthrough a respective one of a plurality of metal-plated apertures 139-1through 139-8 that are provided in the fingers 136. The second end ofeach jackwire contact 140 is mounted to extend upwardly from arespective one of the fingers 138. The second end 146 of each jackwirecontact 140 may extend through a respective one of a plurality ofmetal-plated apertures 139-9 through 139-16 that are provided in thefingers 138. The metal-plated apertures 139-1 through 139-16electrically connect each jackwire contact 140 to respective conductivetraces or other structures on the flexible printed circuit board 130, aswill be discussed in more detail below with reference to FIG. 8.

The first end 142 and the second end 146 of each jackwire contact 140may each be mounted to be substantially perpendicular to a top surface,of the flexible printed circuit board 130 (although they need not be).The middle portion 144 of each jackwire contact 140 may be raised abovethe top surface of the flexible printed circuit board 130 such that agap or spacing exists between a lower surface of the middle portion 144of each jackwire contact 140 and the upper surface of the flexibleprinted circuit board 130. Additionally, the middle portion 144 of eachjackwire contact 140 may define an oblique angle with respect to theplane or planes that are defined by the top surface of the flexibleprinted circuit board 130, as is shown in FIG. 6.

In some embodiments (such as the depicted embodiment), all of thejackwire contacts 140 may have the same profiles. This may simplify themanufacturing process and may also reduce production costs. However, inother embodiments the jackwire contacts 140 may have different profiles.For example, jackwire contacts 140-1, 140-3, 140-5 and 140-7 may have afirst profile, while jackwire contacts 140-2, 140-4, 140-6 and 140-8 mayhave a second profile that is different from the first profile. Thejackwire contact profiles may be designed to reduce coupling betweenadjacent jackwire contacts 140 by reducing the size of the region whereadjacent jackwire contacts 140 are close to each other.

As is shown in FIGS. 4 and 6, the communications insert 120 furtherincludes eight dielectric contact carriers 150-1 through 150-8. Herein,a “contact carrier” refers to a structure that provides mechanicalsupport to a jackwire contact. In the depicted embodiment, each contactcarrier 150 comprises an elongated, generally planar strip of moldedplastic. Each contact carrier 150 extends parallel to the longitudinalaxis of the jack 100, and each contact carrier 150 may be longitudinallyaligned with a respective one of the jackwire contacts 140. The contactcarriers 150 are aligned side-by-side in a row (in numerical order) inthe lateral direction. Each of the dielectric contact carriers 150includes an upwardly-extending protrusion 152. Each of these protrusions152 is aligned underneath a respective one of the fingers 138. The firstend 142 of each jackwire contact 140 extends through a respective one ofthe fingers 136 into an aperture in a top surface of the contact carrier150 that is positioned underneath the jackwire contact 140. The secondend 146 of each jackwire contact 140 extends through a respective one ofthe fingers 138 into an aperture on a respective one of the protrusions152 on the contact carrier 150 that is positioned underneath thejackwire contact 140. The protrusions 152 act to hold the lower surfaceof the flexible printed circuit board 130 above the main upper surfaceof the contact carriers 150 in order to allow the fingers 138 to morefreely flex downwardly when a mating plug is received within the plugaperture 114. While not shown in the figures, it will be appreciatedthat a second, identical, protrusion 152 may also be included on eachcontact carrier 150 directly underneath each respective finger 136, andthat the first end 142 of each respective jackwire contact 140 may bereceived in these respective second protrusions 152.

While only one of the dielectric contact carriers 150 (namely contactcarrier 150-1) is fully illustrated in FIGS. 4 and 6, it will beappreciated that all of the contact carriers 150-1 through 150-8 may beidentical except that the location of the protrusions 152 may beadjusted to be underneath the second end 146 of their mating jackwirecontact 140. While the contact carriers 150 are completely separate fromeach other in the depicted embodiment, it will be appreciated that inother embodiments some of the contact carriers 150 may be connected toeach other.

Each contact carrier 150 may be mounted to move within the jack 100, aswill be discussed in more detail below with respect to FIG. 9. As theends 142, 146 of each jackwire contact 140 are mounted in a respectiveone of the contact carriers 150, each dielectric contact carrier 150 andits respective jackwire contact 140 will move together as a single unitwhen a communications plug is inserted into the plug aperture 114 ofjack 100 and physically engages the jackwire contacts 140.

Referring to FIGS. 6 and 9, it can be seen that the communicationsinsert 120 further includes a spring 160. The spring 160 may comprise acomb-like structure that has a base 162 and eight fingers 164-1 through164-8. The spring 160 may be implemented, for example, as a piece ofresilient metal such as beryllium-copper or phosphor-bronze that ismounted, for example, to a bottom surface of the substrate 122 (oranother substrate or housing piece of the jack 100) by any appropriatemeans. However, it will be appreciated that a wide variety of differentmaterials may be used to form the spring 160, including other metals,plastics, etc., and it will also be appreciated that the spring 160 maybe implemented in many different forms (e.g., as a coiled spring, acantilevered spring, etc.). In the illustrated embodiment, a singlespring 160 is provided that is used for all eight jackwire contacts 140,but it will be appreciated that in other embodiments more than onespring 160 may be provided (e.g., a separate spring 160 could beprovided for each of the jackwire contacts 140).

Each of the contact carriers 150 may be mounted directly on top of arespective one of the eight fingers 164 of spring 160. Alternatively,each finger 164 of the spring may be attached to a side surface of therespective dielectric contact carriers 150. In either case, each finger164 of the spring 160 is connected to a respective one of the jackwirecontacts 140 through a respective one of the contact carriers 150. Eachfinger 164 of the spring 160 may “spring bias” its associated contactcarrier 150 and jackwire contact 140 so that when the contact carrier150 and jackwire contact 140 are pressed down a spring force is appliedthat urges the contact carrier 150 and jackwire contact 140 upwardly toreturn to their normal resting positions.

When a mating plug is received within the plug aperture 114, the plugblades deflect each respective jackwire contact 140 and its associatedcontact carrier 150 downwardly. The contact carriers 150, in turn,deflect each of the eight fingers 164 of spring 160 downwardly. As thespring 160 is resilient, the fingers 164 of the spring 160 exert anupward force on their respective contact carriers 150, thereby forcingeach of the jackwire contacts 140 upwardly to ensure that each jackwirecontact 140 engages its mating plug blade with sufficient contact forceto ensure that a reliable electrical connection is maintained betweenthe eight blades of the mating plug and the jackwire contacts 140 withwhich they respectively mate. The spring 160 may be electricallyisolated by the contact carriers 150 from the jackwire contacts 140 (andhence is not part of the signal current carrying paths).

As the resiliency of the spring 160 provides the contact force (throughthe contact carriers 150) that presses the jackwire contacts 140 againstthe respective blades of a mating plug, the jackwire contacts 140 neednot be mounted in cantilevered fashion, nor must they be resilient(although they may be). Consequently, in some embodiments, the jackwirecontacts 140 may be very short in length, which can significantly reducethe amount of coupling between adjacent jackwire contacts 140, and hencethe amount of offending crosstalk that is generated. For example, thejackwire contacts 140 may each be about 200 mils to about 230 mils inlength, in contrast with typical conventional jackwire contacts whichmay be much longer range, for example, from about 400 mils to about 800mils in length, or even more.

While not shown in the drawings, a plurality of guiding walls may beprovided in, for example, the jack housing 110, that define a pluralityof guiding slots therebetween. A portion of each of the contact carriers150 may be positioned in a respective one of these slots. Each contactcarrier 150 may move up and down within its respective slot in responseto the insertion or removal of a mating plug, but the slots act tomaintain each of the contact carriers 150, and hence the jackwirecontacts 140 mounted thereon, in their proper lateral alignment withinthe plug aperture 114 in order to maintain the jackwire contacts 140 atdesired distances from each other and to ensure that the jackwirecontacts 140 are properly aligned with their mating plug blades.

As shown best in FIGS. 4, 6 and 8, the jackwire contacts 140 may bealigned in two rows in the lateral direction, with jackwire contacts140-2, 140-4, 140-6 and 140-8 mounted in a first row that is fartherforward on the flexible printed circuit board 130 than jackwire contacts140-1, 140-3, 140-5 and 140-7, which are mounted in a second row.

FIG. 8 is a schematic plan view of the flexible printed circuit board130. FIG. 8 more clearly pictures how the slots 133, 134, 135 and 137are used to form the fingers 136-1 through 136-8 and 138-1 through 138-6(note that fingers 136-2 through 136-7 are not numbered in FIG. 8 tosimplify the drawing, but are aligned in numerical order between fingers136-1 and 136-8). FIG. 8 also illustrates the metal-plated apertures139-1 through 139-8 which receive the first end 142 of jackwire contacts140-1 through 140-8, respectively, and metal-plated apertures 139-9through 139-16 that receive the second ends 146 of jackwire contacts140-1 through 140-8, respectively. The first and second ends 142, 146 ofthe jackwire contacts 140 can be permanently mounted into theirrespective metal-plated apertures 139-1 through 139-16 by anyconventional means such as, for example, welding, soldering or includingcompliant pin terminations on the ends 142, 146 of each jackwire contact140. In this fashion, the first end 142 and the second end 146 of eachjackwire contact 140 may be electrically connected to conductivestructures on the flexible printed circuit board 130 in order to allowelectrical signals (and electrical power) to pass between the flexibleprinted circuit board 130 and the respective jackwire contacts 140.

The flexible printed circuit board 130 may act as a signal carryingstructure that passes signals between the eight jackwire contacts 140and respective ones of eight output contacts 170 of the jack 100. Inparticular, as is shown in the schematic diagram of FIG. 8, a pluralityof conductive paths 174-1 through 174-8 are provided in or on theflexible printed circuit board 130. Each conductive path 174 connects arespective one of the metal-plated apertures 139-9 through 139-16 to acorresponding one of a plurality of metal-plated apertures 172-1 through172-8 in order to provide eight conductive paths through the flexibleprinted circuit board 130. Each conductive path 174 may be formed, forexample, as a unitary conductive trace that resides on a single layer ofthe flexible printed circuit board 130 or as two or more conductivetraces that are provided on multiple layers of the flexible printedcircuit board 130 and which are electrically connected throughmetal-filled vias or other layer transferring techniques known to thoseof skill in the art. The conductive traces 174 may be formed ofconventional conductive materials such as, for example, copper, and aredeposited on the flexible printed circuit board 130 via any depositionmethod known to those skilled in this art.

A plurality of crosstalk compensation circuits 178 such as, for example,interdigitated finger capacitors, plate capacitors, inductively couplingtraces and the like may also be provided on and/or within the flexibleprinted circuit board 130. Two exemplary capacitive crosstalkcompensation circuits 178-1, 178-2 in the form of plate capacitors (onlythe upper plate of each plate capacitor is visible) are illustrated inFIG. 8, as are two exemplary inductive crosstalk compensation circuits178-3, 178-4. Either or both the capacitive crosstalk compensationcircuits 178-1, 178-2 and/or the inductive crosstalk compensationcircuits 178-3, 178-4 may be located on portions of the flexible printedcircuit board 130 that move when a plug is inserted into the plugaperture 114 of jack 100. Each of these crosstalk compensation circuitswill be discussed in more detail below.

As shown in FIG. 7, a plurality of output terminals 170-1 through 170-8are also mounted to be in electrical contact with the flexible printedcircuit board 130. In this particular embodiment, the eight outputterminals 170 are implemented as insulation displacement contacts (IDCs)that are mounted in the metal-plated apertures 172-1 through 172-8 (seeFIG. 8) in the flexible printed circuit board 130 and extend through theboard 130 into the mounting substrate 122. As is well known to those ofskill in the art, an IDC is a type of wire connection terminal that maybe used to make mechanical and electrical connection to an insulatedwire conductor. The IDCs 170 may be of conventional construction andneed not be described in detail herein. Any other appropriate outputcontact may be used including, for example, insulation piercingcontacts.

The communications jacks according to embodiments of the presentinvention may exhibit improved crosstalk performance as compared to manyconventional communications jacks.

As is known to those of skill in the art, modern communications jackssuch as RJ-45 jacks typically include single-stage or multi-stagecrosstalk compensation circuits that are designed to inject“compensating” crosstalk that cancels out “offending” crosstalk that isinjected between two differential pairs in a mated communications jackand plug combination due to industry-standardized configurations of theplug blades and the jackwire contacts. However, the compensatingcrosstalk typically cannot be inserted at precisely the same locationswhere the offending crosstalk is injected, and thus the compensatingcrosstalk is typically injected at some delay after the offendingcrosstalk. Unfortunately, for communications signals at higherfrequencies (e.g., at frequencies above 100 MHz and, even more so forfrequencies above 250 MHz or 500 MHz), a significant phase shift mayoccur because of the delay between the locations where the offending andcompensating crosstalk are injected, and because of this phase shift,the compensating crosstalk will not completely cancel out the offendingcrosstalk.

In an effort to address this problem caused by the delay, theaforementioned '358 patent teaches methods of using multi-stagecrosstalk compensation in communications jacks that may, theoretically,completely cancel out an offending crosstalk signal having a specificfrequency. However, since the frequency of the communications signalsthat traverse a plug-jack connection are typically not known in advance,the techniques of the '358 patent may provide good, but not perfect,crosstalk cancellation at other frequencies. Moreover, because of theaforementioned phase shifts, all other things being equal, bettercrosstalk performance can typically be achieved the less offendingcrosstalk that is generated and the closer in time the compensatingcrosstalk is injected to point where the offending crosstalk isinjected.

As is known to those of skill in the art, crosstalk compensationcircuits are typically implemented in communications jacks such as RJ-45jacks capacitive crosstalk compensation circuits and as inductivecrosstalk compensation circuits. Capacitive crosstalk compensationcircuits are most typically implemented as plate capacitors and/or asinterdigitated finger capacitors that are implemented, for example, on aprinted circuit board of the jack or in the jackwire contacts of thejack, although other capacitive crosstalk compensation circuits may beused. Inductive crosstalk compensation circuits are most typicallyimplemented as conductive paths that run side-by-side next to eachother, either in the jackwire contacts or as conductive traces on aprinted circuit board of the jack. Typically, it is desirable toimplement the crosstalk compensation scheme using both inductivecrosstalk compensation circuits and capacitive crosstalk compensationcircuits so that both near end crosstalk and far end crosstalk can becancelled.

The communications jacks according to embodiments of the presentinvention may include a variety of features that either reduce theamount of crosstalk that is injected in the plug-jack mating region, orthat facilitate the injection of compensating crosstalk at a very smalldelay, as will now be explained.

As one example, capacitive crosstalk compensation circuits such ascircuits 178-1, 178-2 are provided in the front portion 131 of theflexible printed circuit board 130. Notably, these capacitive crosstalkcompensation circuits 178-1, 178-2 are attached to the first ends 142 ofthe jackwire contacts, and hence are not on the signal current carryingpath through the jack 100. Consequently, the capacitive crosstalkcompensation may be injected at a very small delay from the plug-jackmating point, as the delay is reduced when the capacitive crosstalkcompensation is not on the signal current carrying path. While theembodiment depicted in the figures only shows capacitive crosstalkcompensation circuits attached between pairs 1 and 3, it will beappreciated that additional crosstalk compensation circuits may beprovided.

The jack 100 is further designed to inject inductive crosstalkcompensation at a short delay from the plug-jack mating point. Theinductive crosstalk compensation is provided in the jack 100 by theinductive crosstalk compensation circuits 178-3, 178-4, each of whichare formed by running two of the conductive traces on the flexibleprinted circuit board close to each other so that the traces inductivelycouple. In order to inject this inductive crosstalk compensation at arelatively small delay, it is desirable to implement the inductivecrosstalk compensation circuit in the flexible printed circuit board 130very close to the second ends 146 of the jackwire contacts 140 (i.e., assoon as possible to the points where the signals enter the flexibleprinted circuit board 130 from the jackwire contacts 140). However, asis shown in FIGS. 4 and 8, the longitudinal slots 137 that are providedbetween the fingers 138 may be relatively long. As such, the shortestpath distance along the flexible printed circuit board 130 between twoof the metal-plated holes 139 that receive the second ends 146 of two ofthe jackwire contacts 140 may be fairly long. For example, as anextended longitudinal slot 137-1 separates fingers 138-1 and 138-2, theshortest path distance between the metal-plated apertures 139-9 and138-10 that are provided on fingers 138-1 and 138-2 may be fairly long,as this shortest path distance must travel all the way around the slot137-1, as is shown graphically by the arrow labeled “d1” in FIG. 8. As aresult, the longitudinal slots 137 may make it difficult to quicklyprovide inductive crosstalk compensation on the flexible printed circuitboard 130 as such inductive compensation is typically implemented byrunning two conductive traces side-by-side on the so that theyinductively couple, and the slots 137 may force a designer to implementsuch inductive crosstalk compensation at a greater distance, and hence agreater delay, from the jackwire contacts 140. As noted above, crosstalkcompensation may be more effective if it may be injected close to theplug jack mating point, and hence this delay in the injection of theinductive crosstalk compensation may make it more difficult toeffectively cancel the crosstalk.

Pursuant to embodiments of the present invention, the second ends 146 oftwo (or more) of the jackwire contacts 140 may be co-mounted on the samefinger 138. In particular, as shown in FIGS. 4 and 8, the second ends146 of jackwire contacts 140-3 and 140-5 are both located on finger138-3, and the second ends of jackwire contacts 140-4 and 140-6 are bothlocated on finger 138-4. This arrangement can significantly reduce theshortest path distance between the metal-plated apertures (e.g.,metal-plated apertures 139-11 and 139-13 that receive the second ends146 of jackwire contacts 140-3 and 140-5, respectively) that areco-located on the same finger 138. For example, as shown in FIG. 8, theshortest path distance between metal-plated apertures 139-11 and 139-13(labeled “d2” in FIG. 8) may be less than half the shortest pathdistance (e.g., distance d1) between two metal-plated apertures 139 thatare not co-located on the same finger 138. The same is true with respectto metal-plated holes 139-12 and 139-14, because their correspondingjackwire contacts 140-4 and 140-6 are also co-located on the same finger138-4.

As shown on FIG. 8, the conductive traces 174-3 and 174-5 that areconnected to the metal-plated apertures 139-11 and 139-13 include aninductive coupling section 178-4 that provides inductive crosstalkcompensation between pairs 1 and 3. Likewise, the conductive traces174-4 and 174-6 that are connected to the metal-plated apertures 139-12and 139-14 include an inductive coupling section 178-3 that alsoprovides inductive crosstalk compensation between pairs 1 and 3. Theinductive coupling sections 178-3, 178-4 are each located a very shortdistance (here distance d2), and hence a short delay, from the jackwirecontacts 140, and thus may provide more effective crosstalkcompensation.

The design of the jackwire contacts 140 may also improve the crosstalkperformance of the jack 100. Most conventional RJ-45 communicationsjacks implement the plug contacts using spring jackwires that areelongated contact wires that are formed of beryllium-copper orphosphor-bronze. These contact wires may be formed to be sufficientlyresilient such that the plug contact will meet industry standardizedspecifications with respect to the contact force that each plug contactapplies to a mating plug blade and/or to ensure that the contact wiresdo not become permanently deformed with use. Typically, relatively longcontact wires must be used in order to ensure that the contact wireprovides the requisite contact force. In contrast, the jackwire contacts140 that may be included in communications jacks according toembodiments of the present invention may be significantly shorter, andthus the signal current carrying path through each of the input contacts140 may be very short in length. In particular, the signal currentcarrying path through each jackwire contact 140 extends from the middleregion 144 of the jackwire contact 140 (i.e., the part of the plugcontact that engages a mating plug blade) to the second end 146 of thecontact 140. In some embodiments, the length of each jackwire contact140 may be between about 200 mils and about 230 mils, which is far lessthan the length of most conventional spring jackwire contacts. As aresult, the coupling, and hence the crosstalk, between adjacent jackwirecontacts 140 may be significantly reduced.

Additionally, as is discussed above, the jackwire contacts 140 may bealigned in two staggered rows in the lateral direction. By aligning thejackwire contacts 140 in two staggered rows, it is possible to furtherreduce the amount of offending crosstalk that is generated between thedifferential pairs. By way of example, in the plug-jack mating region,typically jackwire contact 2 (which is part of pair 2) will couple agreater amount of signal energy onto jackwire contact 140-3 (which ispart of pair 3) than will jackwire contact 140-1 (which is the otherjackwire contact of pair 2), as jackwire contact 140-2 is directlyadjacent to jackwire contact 140-3, while jackwire contact 140-1 ispositioned farther away from jackwire contact 140-3. Consequently, thisunequal coupling by the conductors of pair 2 onto pair 3 results inoffending crosstalk from pair 2 onto pair 3 (and vice versa). Bystaggering jackwire contact 140-2 with respect to jackwire contacts140-1 and 140-3 (i.e., by moving jackwire contact 140-2 forwardly intothe first row), the amount of coupling between jackwire contact 140-2and 140-3 can be reduced, thereby reducing the amount of unequalcoupling from the conductors of pair 2 onto jackwire contact 140-3.Moreover, as jackwire contacts 140-1 and 140-3 are both aligned in thesecond row, the amount of coupling between jackwire contact 140-1 and140-3 is not reduced and, in fact, is increased since jackwire contact140-2 is no longer fully interposed between jackwire contacts 140-1 and140-3. As the coupling from jackwire contact 140-1 onto jackwire contact140-3 cancels out the coupling from jackwire contact 140-2 onto jackwirecontact 140-3, this further reduces the amount of offending crosstalkthat is generated between pair 2 and pair 3. Similar beneficialreductions in the amount of offending crosstalk may be achieved on eachadjacent pair combination. Thus, the staggering of the input contacts140 into first and second rows may further reduce the amount ofoffending crosstalk generated in the jack 100.

FIG. 10 is a schematic perspective view of a portion of a flexibleprinted circuit board 230 according to further embodiments of thepresent invention that may be used in the communications jack of FIG. 3.The flexible printed circuit board 230 may be used in place of theflexible printed circuit board 130 in jack 100. As the flexible printedcircuit board 230 and the flexible printed circuit board 130 are quitesimilar, the discussion that follows will focus on differences betweenthese two printed circuit board configurations. The flexible printedcircuit board 230 may be used in the communications insert 120 discussedabove in conjunction with the substrate 122, the jackwire contacts 140,the dielectric contact carriers 150, the spring 160 and the outputcontacts 170 that are discussed above.

As shown in FIG. 10, the flexible printed circuit board 230 includes apair of longitudinal slots 233 that “decouple” a front portion 231 ofthe flexible printed circuit board 230 from the back portion 232, and alateral slot 234 that extends between the pair oflongitudinally-extending slots 233. In an alternative embodiment, theslots 233 may be omitted and the lateral slot 234 may be extended allthe way to the side edges of the flexible printed circuit board 230 inorder to cut the flexible printed circuit board 230 into two separatepieces (namely a front piece 231 and a rear piece 232).

The flexible printed circuit board 230 includes one or more dielectriclayers. A plurality of conductive traces are disposed on various ofthese layers. These conductive traces are used to form conductive paths274 that act as transmission mediums for signals that pass between thejackwire contacts 140 and the respective output contacts 170 of a jackthat uses the flexible printed circuit board 230. In the depictedembodiment, the flexible printed circuit board 230 includes onedielectric layer with conductive traces and other conductive structuresdisposed on either side thereof (i.e., on the top and bottom sides ofthe flexible printed circuit board 230). However, in other embodiments,more than one dielectric layer may be included and conductive tracesand/or elements may be included on one or more intermediate layers.

The flexible printed circuit board 232 includes six longitudinal slots237 in the rear portion thereof that define a plurality of fingers 238.As these slots 237 and fingers 238 are identical to the slots 137 andthe fingers 138 that are provided on flexible printed circuit board 130they will not be described further herein.

The flexible printed circuit board 230 further includes a plurality ofslots 235-1 through 235-5. Slots 235-1, 235-2, 235-4 and 235-5 may beessentially identical to slots 135-1, 135-2, 135-6 and 135-7 of theflexible printed circuit board 130 discussed above. These slots 235-1,235-2, 235-4 and 235-5 define four rearwardly facing fingers 236-1,236-2, 236-5 and 236-6. Slot 235-3 (along with slots 235-2 and 235-4)defines two additional fingers 236-3 and 236-4 that have bothlongitudinal and lateral components.

The jackwire contacts 140 are mounted on the flexible printed circuitboard 230 by inserting the first end 142 of each jackwire contact 140into one of a plurality of metal-plated apertures 239 that are providedin the fingers 236 and by inserting the second end 146 of each jackwirecontact 140 into a respective one of a plurality of metal-platedapertures 239 that are provided in the fingers 238. As shown in FIG. 10,conductive paths 274 are connected to metal-plated apertures 239provided on fingers 238 that electrically connect each jackwire contact140 to the respective output terminals 170 (not visible in FIG. 10).

As discussed above with respect to fingers 136 and 138 of the flexibleprinted circuit board 130 of FIG. 4, the fingers 236 and 238 areprovided so that the jackwire contacts 140 may move relativelyindependent of each other and, in particular, be depressed a differentdistance downwardly when a mating plug is received within the jack 100.However, as is discussed above with respect to FIGS. 4 and 8, thelongitudinal slots 137 that are used to form the fingers 138 may berelatively long, and hence make it difficult to quickly provideinductive crosstalk compensation on the flexible printed circuit board130. Accordingly, the second ends 146 of both jackwire contacts 140-3and 140-5 are co-located on finger 138-3, and the second ends of bothjackwire contacts 140-4 and 140-6 are co-located on finger 138-4. Thesame design is followed in the embodiment of FIG. 10 with respect tofingers 238-3 and 238-4. This arrangement facilitates implementing twoinductive crosstalk compensation circuits 278-3 and 278-4 that provideinductive crosstalk compensation between pairs 1 and 3 at a very smalldelay from the plug-jack mating point, as can be seen in FIG. 10.

In the embodiment of FIG. 10, the longitudinal fingers 136-3 through136-6 from the embodiment of FIGS. 4 and 8 are replaced with fingers236-3 and 236-4 that each have both longitudinal and transversecomponents. This design allows the capacitive crosstalk compensationcircuits 278-1 and 278-2 to be implemented significantly closer to theconductive vias 239 on finger 236-3 (for capacitive crosstalkcompensation circuit 278-1) and to the conductive vias 239 on finger236-4 (for capacitive crosstalk compensation circuit 278-2), and hencecloser to the plug-jack mating point. This may potentially provide moreeffective crosstalk cancellation.

In the embodiments described above, the jackwire contacts 140 aremounted on the flexible printed circuit boards 130, 230 by inserting thefirst end 142 of each jackwire contact 140 into one of a plurality ofmetal-plated apertures 139, 239 that are provided in the fingers 136,236, and by inserting the second end 146 of each jackwire contact 140into a respective one of a plurality of metal-plated apertures 239 thatare provided in the fingers 138, 238 such that both ends 142, 146 ofeach jackwire contact 140 are mounted on the flexible printed circuitboard 130, 230 (or potentially on another printed circuit board ormounting substrate). However, it will be appreciated that, in furtherembodiments of the present invention, sliding contact arrangements maybe used on at least one end of some or all of the jackwire contacts 140.

For example, referring to FIG. 4, in further embodiments of the presentinvention, some or all of the metal-plated apertures 139-9 through139-16 may be replaced with conductive (e.g., copper) pads that areprovided on the top surface of the fingers 138 in the same positions asthe metal plated apertures 139-9 through 139-16. The second end 146 ofthe jackwire contacts 140 may be designed to have a pad mating regionthat is configured to make physical and electrical contact with arespective one of these contact pads when a mating plug is receivedwithin the plug aperture 114 of jack 100. The forces applied by the plugblades on the jackwire contacts 140 and the countervailing force appliedby the spring 160 on the fingers 138 may ensure that the second end 146of each jackwire contact 140 firmly mates with its respective contactpad to provide a good electrical connection therebetween. Thus, in someembodiments, both ends of the jackwire contacts 140 need not bepermanently mounted on the flexible printed circuit board or othermounting substrate.

While various of the above-described communications jacks include aflexible printed circuit board that may be cut in two to form twoflexible printed circuit boards, it will be appreciated that embodimentsof the present invention are not limited to such an implementation. Forexample, in some embodiments, the flexible printed circuit board may notbe cut so that the jack includes a single flexible printed circuitboard. In other embodiments, a flexible printed circuit board may hold,for example, the rear ends of the jackwire contacts (i.e., the ends thatare closest to the IDCs) while a conventional printed circuit board mayhold the front ends of the jackwire contacts. In still otherembodiments, a flexible printed circuit board may hold, for example, therear ends of the jackwire contacts while the front ends of the jackwirecontacts may be mounted in another mounting substrate such as, forexample, a piece of the jack housing or a dielectric block. In stillother embodiments, one or more composite flexible printed circuit boardsmay be used such as, for example, a rigid/flex printed circuit boardthat has a flexible portion and a rigid portion. For example, theflexible printed circuit board that receives the rear ends of thejackwire contacts could be implemented using a rigid/flex printedcircuit board instead, with the flexible portion receiving the rear endsof the jackwire contacts and the rigid portion receiving the IDCs orother output terminals. This may simplify mechanically and electricallyconnecting the output terminals to the printed circuit board and/orprovide a more robust connection between the output terminals and theprinted circuit board. It will also be appreciated that more than twoprinted circuit boards may be used and that not all of the front (orrear) ends of the jackwire contacts need be mounted in the same printedcircuit board or other mounting substrate.

While embodiments of the present invention have primarily been discussedherein with respect to communications jacks that include eightconductive paths that are arranged as four differential pairs ofconductive paths, it will be appreciated that the concepts describedherein are equally applicable to jacks that include other numbers ofdifferential pairs.

While the present invention has been described above primarily withreference to the accompanying drawings, it will be appreciated that theinvention is not limited to the illustrated embodiments; rather, theseembodiments are intended to fully and completely disclose the inventionto those skilled in this art. In the drawings, like numbers refer tolike elements throughout. Thicknesses and dimensions of some componentsmay be exaggerated for clarity.

Spatially relative terms, such as “under”, “below”, “lower”, “over”,“upper”, “top”, “bottom” and the like, may be used herein for ease ofdescription to describe one element or feature's relationship to anotherelement(s) or feature(s) as illustrated in the figures. It will beunderstood that the spatially relative terms are intended to encompassdifferent orientations of the device in use or operation in addition tothe orientation depicted in the figures. For example, if the device inthe figures is turned over, elements described as “under” or “beneath”other elements or features would then be oriented “over” the otherelements or features. Thus, the exemplary term “under” can encompassboth an orientation of over and under. The device may be otherwiseoriented (rotated 90 degrees or at other orientations) and the spatiallyrelative descriptors used herein interpreted accordingly.

Well-known functions or constructions may not be described in detail forbrevity and/or clarity. As used herein the expression “and/or” includesany and all combinations of one or more of the associated listed items.

The terminology used herein is for the purpose of describing particularembodiments only and is not intended to be limiting of the invention. Asused herein, the singular forms “a”, “an” and “the” are intended toinclude the plural forms as well, unless the context clearly indicatesotherwise. It will be further understood that the terms “comprises”,“comprising”, “includes” and/or “including” when used in thisspecification, specify the presence of stated features, operations,elements, and/or components, but do not preclude the presence oraddition of one or more other features, operations, elements,components, and/or groups thereof.

Unless otherwise defined, all terms (including technical and scientificterms) used herein have the same meaning as commonly understood by oneof ordinary skill in the art to which this invention belongs. It will befurther understood that terms, such as those defined in commonly useddictionaries, should be interpreted as having a meaning that isconsistent with their meaning in the context of the relevant art andwill not be interpreted in an idealized or overly formal sense unlessexpressly so defined herein.

Herein, the terms “attached”, “connected”, “interconnected”,“contacting”, “mounted” and the like can mean either direct or indirectattachment or contact between elements, unless stated otherwise.

Although exemplary embodiments of this invention have been described,those skilled in the art will readily appreciate that many modificationsare possible in the exemplary embodiments without materially departingfrom the novel teachings and advantages of this invention. Accordingly,all such modifications are intended to be included within the scope ofthis invention as defined in the claims. The invention is defined by thefollowing claims, with equivalents of the claims to be included therein.

1. A communications jack, comprising: a first jackwire contact; a secondjackwire contact; a third jackwire contact; and a flexible substratethat has a first finger and a second finger, wherein the first jackwirecontact and the third jackwire contact are each configured toelectrically connect to respective first and third conductive structureson the first finger and the second jackwire contact is configured toelectrically connect to a second conductive structure on the secondfinger.
 2. The communications jack of claim 1, wherein the first andthird conductive structures are respective first and third metal-platedapertures that extend through the first finger, wherein the secondconductive structure is a second metal-plated aperture that extendsthrough the second finger, and wherein the first, second and thirdjackwire contacts are mounted in the respective first, second and thirdmetal-plated apertures.
 3. The communications jack of claim 1, whereinthe first and third conductive structures are respective first and thirdcontact pads that are located on the first finger, wherein the secondconductive structure is a second contact pad that is located on thesecond finger, and wherein the first, second and third jackwire contactsare configured to engage the respective first, second and third contactpads when a mating plug is received within a plug aperture of thecommunications jack.
 4. The communications jack of claim 2, wherein theflexible substrate comprises a flexible printed circuit board.
 5. Thecommunications jack of claim 4, wherein the first jackwire contact andthe third jackwire contact are substantially aligned in a first row, andwherein the second jackwire contact is substantially aligned with atleast one additional jackwire contact in a second row that is offsetfrom the first row.
 6. The communications jack of claim 4, wherein theflexible printed circuit board includes a first conductive trace that iselectrically connected to the first jackwire contact, a secondconductive trace that is electrically connected to the second jackwirecontact, and a third conductive trace that is electrically connected tothe third jackwire contact, wherein the first conductive trace crossesunder the second jackwire contact.
 7. The communications jack of claim1, wherein the first through third jackwire contacts are substantiallyrigid jackwire contacts.
 8. The communications jack of claim 1, furthercomprising: a housing that includes a plug aperture; and an inductivecrosstalk compensation circuit that is located on a portion of theflexible substrate that moves when a mating plug is received within theplug aperture.
 9. The communications jack of claim 2, further comprisinga first dielectric contact carrier, a second dielectric contact carrierand a third dielectric contact carrier, wherein the first jackwirecontact is mounted in the first dielectric contact carrier through thefirst finger, the second jackwire contact is mounted in the seconddielectric contact carrier through the second finger, and the thirdjackwire contact is mounted in the third dielectric contact carrierthrough the first finger.
 10. The communications jack of claim 9,further comprising a spring, wherein at least the first dielectriccontact carrier is interposed between the first jackwire contact and thespring so that the spring spring-biases the first jackwire contact. 11.The communications jack of claim 10, wherein the spring is electricallyisolated from the first jackwire contact.
 12. The communications jack ofclaim 1, wherein a first end of the first jackwire contact and a firstend of the third jackwire contact are each mounted on the first fingerand a first end of the second jackwire contact is mounted on the secondfinger, and wherein a second end of the first jackwire contact ismounted on a third finger of the flexible substrate, and a second end ofthe second jackwire contact is mounted on a fourth finger of theflexible substrate.
 13. The communications jack of claim 12, wherein aslot in the flexible substrate separates the first and second fingersfrom the third, fourth and fifth fingers.
 14. The communications jack ofclaim 9, wherein each of the first, second and third dielectric contactcarriers is configured so that it may move a different amount than otherof the first through third dielectric contact carriers in response to aplug being inserted into a plug aperture in a housing of thecommunications jack.
 15. A communications jack, comprising: a firstsubstrate; a second substrate; and a plurality of jackwire contacts,wherein a first end of each jackwire contact is mounted in the firstsubstrate and the second end of each jackwire contact is electricallyconnected to the second substrate; wherein at least one of the firstsubstrate or the second substrate comprises a flexible printed circuitboard, and wherein the flexible printed circuit board is configured tomove in response to movement of the jackwire contacts.
 16. Thecommunications jack of claim 15, wherein the second end of each jackwirecontact is mounted in a respective one of a plurality of conductive viasin the second substrate.
 17. The communications jack of claim 16,wherein the first substrate is a front portion of the flexible printedcircuit board and the second substrate is a back portion of the flexibleprinted circuit board.
 18. The communications jack of claim 17, whereinthe flexible printed circuit board includes a slot that extends under amiddle portion of each of the plurality of jackwire contacts.
 19. Thecommunications jack of claim 16, wherein the first substrate is theflexible printed circuit board and the second substrate is differenttype of mounting substrate.
 20. The communications jack of claim 15,wherein a first subset of the plurality of jackwire contacts issubstantially aligned in a first row and a second subset of theplurality of jackwire contacts is substantially aligned in a second rowthat is offset from the first row.
 21. The communications jack of claim16, wherein the flexible printed circuit board includes a plurality offingers, and wherein at least one end of each of the jackwire contactsis mounted on one of the plurality of fingers.
 22. The communicationsjack of claim 21, further comprising a capacitive crosstalk compensationcircuit that is on the flexible printed circuit board and connected to anon-signal current carrying end of a first of the plurality of jackwirecontacts, and an inductive crosstalk compensation circuit that is on theflexible printed circuit board and connected to a signal currentcarrying end of the first of the plurality of jackwire contacts that isopposite the non-signal current carrying end.
 23. The communicationsjack of claim 22 wherein a signal carrying end of a second of theplurality of jackwire contacts is on the same finger of the flexibleprinted circuit board as is the signal carrying end of the first of theplurality of jackwire contacts.
 24. The communications jack of claim 16,wherein the communications jack is an RJ-45 jack, and wherein theplurality of jackwire contacts comprises eight contacts that arearranged as four differential pairs of contacts.
 25. The communicationsjack of claim 16, further comprising an inductive crosstalk compensationcircuit that is located on a portion of the flexible printed circuitboard that moves when a mating plug is received within thecommunications jack. 26-45. (canceled)